The Spreadtrum hardware spinlock device can provide hardware assistance
for synchronization between the multiple subsystems.
Signed-off-by: Baolin Wang <baolin.w...@spreadtrum.com>
---
drivers/hwspinlock/Kconfig | 9 ++
drivers/hwspinlock/Makefile | 1 +
drivers/hwspinlock/sprd_hwspinlock.c | 243 ++++++++++++++++++++++++++++++++++
3 files changed, 253 insertions(+)
create mode 100644 drivers/hwspinlock/sprd_hwspinlock.c
diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index 73a4016..25304e0 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -53,4 +53,13 @@ config HSEM_U8500
If unsure, say N.
+config HWSPINLOCK_SPRD
+ tristate "SPRD Hardware Spinlock device"
+ depends on ARCH_SPRD
+ select HWSPINLOCK
+ help
+ Say y here to support the SPRD Hardware Spinlock device.
+
+ If unsure, say N.
+
endmenu
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index 6b59cb5a..03c442f 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o
obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o
obj-$(CONFIG_HWSPINLOCK_SIRF) += sirf_hwspinlock.o
obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o
+obj-$(CONFIG_HWSPINLOCK_SPRD) += sprd_hwspinlock.o
diff --git a/drivers/hwspinlock/sprd_hwspinlock.c
b/drivers/hwspinlock/sprd_hwspinlock.c
new file mode 100644
index 0000000..898738f
--- /dev/null
+++ b/drivers/hwspinlock/sprd_hwspinlock.c
@@ -0,0 +1,243 @@
+/*
+ * Spreadtrum hardware spinlock driver
+ * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/hwspinlock.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "hwspinlock_internal.h"
+
+/* hwspinlock registers definition */
+#define HWSPINLOCK_RECCTRL 0x4
+#define HWSPINLOCK_TTLSTS 0x8
+#define HWSPINLOCK_FLAG0 0x10
+#define HWSPINLOCK_FLAG1 0x14
+#define HWSPINLOCK_FLAG2 0x18
+#define HWSPINLOCK_FLAG3 0x1c
+#define HWSPINLOCK_MASTERID(_X_) (0x80 + 0x4 * (_X_))
+#define HWSPINLOCK_TOKEN(_X_) (0x800 + 0x4 * (_X_))
+#define HWSPINLOCK_VERID 0xFFC
+
+/* untoken lock value */
+#define HWSPINLOCK_NOTTAKEN 0x55aa10c5
+/* bits definition of RECCTRL reg */
+#define HWSPINLOCK_ID 0x0
+#define HWSPINLOCK_USER_BITS 0x1
+
+/* hwspinlock number */
+#define SPRD_HWLOCKS_NUM 32
+
+struct sprd_hwspinlock_dev {
+ void __iomem *base;
+ struct clk *clk;
+ unsigned char status[SPRD_HWLOCKS_NUM];
+ struct hwspinlock_device bank;
+};
+
+static const struct of_device_id sprd_hwspinlock_of_match[] = {
+ { .compatible = "sprd,hwspinlock-r3p0",},
+ { /* sentinel */ }
+};
+
+static struct sprd_hwspinlock_dev *sprd_lock_to_dev(struct hwspinlock *lock)
+{
+ struct hwspinlock_device *hwbank;
+ unsigned int lock_id = hwlock_to_id(lock);
+
+ hwbank = container_of(lock, struct hwspinlock_device, lock[lock_id]);
+ return container_of(hwbank, struct sprd_hwspinlock_dev, bank);
+}
+
+/* set the hardware spinlock record type */
+static void sprd_set_hwspinlock_record(struct sprd_hwspinlock_dev *sprd_hwlock,
+ unsigned int type)
+{
+ writel_relaxed(type, sprd_hwlock->base + HWSPINLOCK_RECCTRL);
+}
+
+/* get the hardware spinlock master/user id */
+static unsigned int sprd_get_hwspinlock_id(struct sprd_hwspinlock_dev
*sprd_hwlock,
+ unsigned int lock_id)
+{
+ return readl_relaxed(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));
+}
+
+/* record the hardware spinlock status */
+static int sprd_record_hwspinlock_sts(struct hwspinlock *lock)
+{
+ struct sprd_hwspinlock_dev *sprd_hwlock = sprd_lock_to_dev(lock);
+ unsigned int lock_id = hwlock_to_id(lock);
+ unsigned char status;
+
+ if (lock_id >= SPRD_HWLOCKS_NUM) {
+ dev_err(sprd_hwlock->bank.dev, "lock id is out of the range\n");
+ return -ENXIO;
+ }
+
+ /* get the hardware spinlock status */
+ status = !!(readl_relaxed(sprd_hwlock->base + HWSPINLOCK_TTLSTS) &
+ BIT(lock_id));
+
+ sprd_hwlock->status[lock_id] = status;
+ return 0;
+}
+
+/* try to lock the hardware spinlock */
+static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
+{
+ struct sprd_hwspinlock_dev *sprd_hwlock = sprd_lock_to_dev(lock);
+ void __iomem *addr = lock->priv;
+
+ if (!readl_relaxed(addr))
+ goto locked;
+
+ dev_warn(sprd_hwlock->bank.dev,
+ "hwspinlock [%d] lock failed and master/user id = %d!\n",
+ hwlock_to_id(lock),
+ sprd_get_hwspinlock_id(sprd_hwlock, hwlock_to_id(lock)));
+ return 0;
+
+locked:
+ sprd_record_hwspinlock_sts(lock);
+ return 1;
+}
+
+/* unlock the hardware spinlock */
+static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
+{
+ void __iomem *lock_addr = lock->priv;
+
+ writel_relaxed(HWSPINLOCK_NOTTAKEN, lock_addr);
+ sprd_record_hwspinlock_sts(lock);
+}
+
+/* The specs recommended below number as the retry delay time */
+static void sprd_hwspinlock_relax(struct hwspinlock *lock)
+{
+ ndelay(10);
+}
+
+static const struct hwspinlock_ops sprd_hwspinlock_ops = {
+ .trylock = sprd_hwspinlock_trylock,
+ .unlock = sprd_hwspinlock_unlock,
+ .relax = sprd_hwspinlock_relax,
+};
+
+static int sprd_hwspinlock_probe(struct platform_device *pdev)
+{
+ struct sprd_hwspinlock_dev *sprd_hwlock;
+ struct hwspinlock *lock;
+ struct resource *res;
+ int i, ret;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ sprd_hwlock = devm_kzalloc(&pdev->dev,
+ sizeof(struct sprd_hwspinlock_dev) +
+ SPRD_HWLOCKS_NUM * sizeof(*lock),
+ GFP_KERNEL);
+ if (!sprd_hwlock)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sprd_hwlock->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(sprd_hwlock->base))
+ return PTR_ERR(sprd_hwlock->base);
+
+ sprd_hwlock->clk = of_clk_get_by_name(pdev->dev.of_node, "enable");
+ if (IS_ERR(sprd_hwlock->clk)) {
+ dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
+ return PTR_ERR(sprd_hwlock->clk);
+ }
+
+ clk_prepare_enable(sprd_hwlock->clk);
+
+ /* set the hwspinlock to record user id to identify subsystems */
+ sprd_set_hwspinlock_record(sprd_hwlock, HWSPINLOCK_USER_BITS);
+
+ for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
+ lock = &sprd_hwlock->bank.lock[i];
+ lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
+ }
+
+ platform_set_drvdata(pdev, sprd_hwlock);
+ pm_runtime_enable(&pdev->dev);
+
+ ret = hwspin_lock_register(&sprd_hwlock->bank, &pdev->dev,
+ &sprd_hwspinlock_ops, 0, SPRD_HWLOCKS_NUM);
+ if (ret) {
+ dev_err(&pdev->dev, "hwspinlock register failed!\n");
+ pm_runtime_disable(&pdev->dev);
+ clk_disable_unprepare(sprd_hwlock->clk);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int sprd_hwspinlock_remove(struct platform_device *pdev)
+{
+ struct sprd_hwspinlock_dev *sprd_hwlock = platform_get_drvdata(pdev);
+ int ret;
+
+ ret = hwspin_lock_unregister(&sprd_hwlock->bank);
+ if (ret) {
+ dev_err(&pdev->dev, "hwspinlock unregister failed: %d\n", ret);
+ return ret;
+ }
+
+ pm_runtime_disable(&pdev->dev);
+ clk_disable_unprepare(sprd_hwlock->clk);
+ return 0;
+}
+
+static struct platform_driver sprd_hwspinlock_driver = {
+ .probe = sprd_hwspinlock_probe,
+ .remove = sprd_hwspinlock_remove,
+ .driver = {
+ .name = "sprd_hwspinlock",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
+ },
+};
+
+static int __init sprd_hwspinlock_init(void)
+{
+ return platform_driver_register(&sprd_hwspinlock_driver);
+}
+postcore_initcall(sprd_hwspinlock_init);
+
+static void __exit sprd_hwspinlock_exit(void)
+{
+ platform_driver_unregister(&sprd_hwspinlock_driver);
+}
+module_exit(sprd_hwspinlock_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
+MODULE_AUTHOR("Baolin Wang <baolin.w...@spreadtrum.com>");
+MODULE_AUTHOR("Lanqing Liu <lanqing....@spreadtrum.com>");
+MODULE_AUTHOR("Long Cheng <aiden.ch...@spreadtrum.com>");
--
1.7.9.5
